XSS in Opnsense

CVE-2019-25371

OPNsense 19.1 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject malicious scripts by exploiting insufficient input validation in the host parameter. Attackers can submit crafted POST requests to the diag_ping.php endpoint with script payloads in the host parameter to execute arbitrary JavaScript in users' browsers.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.002 (15.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2019-25371?
CVE-2019-25371 is a medium-severity vulnerability in Opnsense, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-02-15.
How severe is CVE-2019-25371?
Medium severity. CVSS v3 base score is 6.1 out of 10.